Blood lipid components such as cholesterols, neutral fats, phospholipids or free fatty acids are in the form of water-soluble lipoproteins in the blood, which are classified into very-low-density lipoprotein (VLDL), low-density lipoprotein (LDL) and high-density lipoprotein (HDL) by the difference of density. Hyperlipemia is in a status of higher blood concentration of these lipid components which is caused by abnormal lipoprotein metabolism in the body than the normal concentration. When the status of hyperlipemia is continued for a long term, cholesterol and the like tend to deposit into the artery wall, and it has been found by many investigations and epidemiological research that atherosclerosis such as myocardial infarction, angina pectoris or cerebral infarction originates and develops. Accordingly, it is important to lower the blood concentration of these lipid components to the normal concentration for treating hyperlipemia, and it is important to maintein the normal concentration for preventing hyperlipemia.
Taurine (aminoethylsulfonic acid) is a sulfur-containing amino acid having a very simple chemical structure with a molecular weight of 125.14, and known to have various pharmacological properties, over a broad area beginning with central nervous system, circulatory system and hepatobiliary system. Concerning the properties of taurine to the cholesterol metabolism, there are also known the lowering effect of serum cholesterol via cholagogic function and inhibition of gallstone formation by cholesterol.
.gamma.-Oryzanol is known to have the properties to inhibit the absorption of cholesterol and improve the lipoprotein metabolism.
For treating hyperlipemia at the present time, dietetic therapy is first applied, and when it is not sufficiently effective, drug theraphy needs to be applied.
Recently, there are some pharmaceutical drugs of hyperlipemia with different mechanism of action (absorption inhibition, excretion acceleration and synthesis inhibition), but they have a problem of the side-effects, main examples of which are leukocyte decrease, hepatic enlargement, gastrointestinal troubles, sexuality reduction, etc. Accordingly, a pharmaceutical drug for treating or preventing hyperlipemia without side-effects is desirable.
In view of preventive medicine, a desired drug for preventing the origination of hyperlipemia is one which maintains the low blood concentration of lipid components (e.g. cholesterols, neutral fats, phospholipids and free fatty acids), has no side-effect, and can be administered safely for a long term.
An object of the present invention is to provide a pharmaceutical preparation of treating or preventing hyperlipemia which is safe even if applied for a long term.